Nuclear morphometry and chromatin texture changes in hepatocellular carcinoma samples may predict outcomes of liver transplanted patients.

BACKGROUND: Nuclear changes are typical in the carcinogenesis of hepatocellular carcinoma (HCC). Morphometry and chromatin texture analysis are quantitative methods for their quantification. In this study, we analyzed nuclear morphometry and chromatin texture parameters in samples of hepatocellular carcinoma from liver transplant patients and their associations with clinicopathologic variables. METHODS: Samples of HCC and adjacent tissue from 34 individuals were collected in tissue microarray blocks. Stained slides were microphotographed using an optical microscope and nuclear parameters analyzed in ImageJ (FracLac plug-in). ROC curve analysis was used to find accurate cut-offs for differentiation of neoplastic and non-neoplastic cells. The inter-rater agreement was also evaluated. RESULTS: Nuclear morphometric and textural differences were observed between the samples of HCC and adjacent tissue of liver transplant patients. Lower mean gray value (p = 0.034) and Feret diameter (p = 0.024) were associated with higher Model for End-Stage Liver Disease (MELD) scores. Nuclei with larger area (p = 0.014) and larger Feret diameter (p = 0.035) were associated with lower survival. Lower aspect ratio was associated with HCC recurrence after the transplant (p = 0.048). The cut-off of 1.13 µm (p = < 0.001) for aspect ratio and cut-off of 21.15 µm (p = 0.038) for perimeter were established for the differentiation of neoplastic and non-neoplastic cells. The morphometric analysis was reproducible to area, circularity, Feret diameter, mean gray value and aspect ratio between observers (p = < 0.001). CONCLUSIONS: Nuclear morphometric differences between the HCC and the adjacent tissue samples were associated with prognostic variables (MELD scores, recurrence and survival) and may predict liver transplant patients' outcomes.

Application of broad-range bacterial PCR amplification and direct sequencing on the diagnosis of neonatal sepsis

Primers universais, que amplificam regiões conservadas de rDNA 23S, foram utilizados para analisar 306 amostras de cultivo de sangue obtidas de 295 neonatos com um ano ou menos de idade admitidos em unidades hospitalares de tratamento intensivo. O diagnóstico molecular baseado em seqüenciamento dos produtos de PCR foi comparado com os resultados obtidos do cultivo das amostras de sangue. Os resultados foram concordantes para 277 (90.5 per center) das 306 amostras testadas, incluindo 263 amostras PCR-negativo e cultura-negativa e 29 amostras cultura-positiva e PCR-positivo. Comparado com o método de cultivo, a técnica de PCR combinada com seqüenciamento, apresentou maior especificidade, 88 per center e 96,3 per center respectivamente, com valores preditivos positivos e negativos de 74,3 e 98,5 per center respectivamente. Concluímos que a técnica baseada em PCR utilizando amostras de cultivo de sangue, obtidas de neonatos com suspeita de sepse bacteriana, apresenta boa correlação com os métodos de cultivo convencionais. A metodologia de PCR/seqüenciamento apresenta aplicabilidade como técnica complementar para o diagnóstico da sepse neonatal. Esta metodologia fácil de ser executada fornece resultados confiáveis podendo ser recomendada para utilização no diagnóstico de amostras obtidas durante o tratamento antimicrobiano especialmente quando o resultado do cultivo permanece negativo. Apresenta, também, potencial de utilização na identificação de espécies bacterianas com problemas de classificação pelos métodos convencionais microbiológicos.